The application of softening agents during the finishing of textiles has been practiced for many years. Textile fabrics treated with durable press resin require treatment with softening agents to achieve commercially acceptable hand, strength, and wrinkle recovery.
A number of silicone compounds have been employed as softening agents in the prior art. Usually, these are reactive or non-reactive silicone fluids which are applied in the form of emulsions. They are generally more economical to use than the available organic softening agents.
In some instances, the silicones, which have been employed have contained reactive groups which crosslink on the fabric to achieve a high degree of durability. One such reactive silicone softening agent is an epoxy-modified polydimethyl-siloxane which is described in U.S. Pat. No. 3,511,699. Other such reactive softening agents are two-component systems comprised of silanol endblocked silicone oil emulsions and methyl trimethoxysilane crosslinkers or methyl hydrogen silicone crosslinkers. The two components are premixed immediately prior to their application to the fabric.
The above mentioned reactive silicone fluids which are employed as softening agents and which impart durable softness are hydrophobic in nature. Hydrophobicity is undesirable in many textile applications because it contributes to fabric soiling and it is believed to inhibit washing effectiveness. Moreover, the hydrophobicity of these softening agents inhibits the absorption of body moisture in clothing fabrics, and thus can cause the wearer to experience a damp sensation.
Silicone glycol nonionic type copolymers, such as those described in U.S. Pat. No. 3,992,332, which are hydrophilic in nature, can be blended with anionic phosphate esters and employed as softening agents in fabric laundering. But, these hydrophilic softeners are non-crosslinking. Consequently, the softness which they impart is not highly durable and the softener must be reapplied in subsequent launderings.
The textile art is seeking an effective softening treatment which is at once highly permanent, hydrophilic, and economical to use.